Firebomb (10)
I believe the answer is:
incendiary
'firebomb' is the definition.
(I know that firebomb can be written as incendiary)
This is all the clue.
(Other definitions for incendiary that I've seen before include "of a provocative nature" , "tending to stir up trouble" , "getting people excited" , "Inciting riot" , "Arsonist" .)